四氢生物蝶呤保存液对Ⅱ型糖尿病患者大隐静脉氧化应激的影响

Effects of tetrahydrobiopterin preservation solution on oxidative stress in great saphenous vein grafts of patients with type 2 diabetes mellitus

目的观察四氢生物蝶呤（BH4）保存液对Ⅱ型糖尿病（T2MD）患者大隐静脉氧化应激的影响。方法取22例T2MD（实验组）及20例无T2MD（对照组）患者的大隐静脉。分别用自体肝素化血液、含10μmol／LBH4或含100μmol／LN．硝基-L-精氨酸甲酯（L—NAME）的自体肝素化血液浸泡1h后，用光泽精增强化学发光法检测血管NADPH氧化酶活性和超氧阴离子水平。结果浸泡前，实验组NADPH氧化酶及超氧阴离子[（304．1±32．4）次／μg、（1821．2±322．3）次／（min·mg）]均明显高于对照组[（253．5±29．8）7次／μg、（1563．5±272．4）次／（min·mg），P〈0．05]；与浸泡前比较，实验组超氧阴离子经BH4和L—NAME浸泡后均明显降低[（1607．4±279．5）、（1683．7±267．9）次／（min·mg），P〈0．05]，对照组经BH4浸泡后差异无统计学意义（P〉0．05），经L—NAME浸泡后明显升高[（1721．2±329．8）次／（min·mg），P〈0．05]，两组经自体肝素化血液浸泡后差异均无统计学意义（P〉0．05）。结论T2MD加重大隐静脉桥的氧化应激反应，BH4保存液能改善内皮一氧化氮合酶（NOS）功能而有助于减轻此反应。

Objective To observe the effect of tetrahydrobiopterin （BH4） preservation solution on oxidative stress in great saphenous vein grafts of patients with type 2 diabetes mellitus （T2MD）. Methods Segments of great saphenous vein were collected from 22 patients with T2MD （test group） and 20 patients without T2MD （control group）. After incubation in heparinized blood, heparinized blood plus BH4 （10 μmol/L） or NG-nitro-L-arginine methyl ester （L-NAME, 100 μmol/L） separately, NADPH oxidase enzymatic activity and superoxide anion levels were quantified by lucigenin-enhanced chemiluminescence. Resuits NADPH oxidase activity and superoxide anion levels were significantly elevated in test group [ （304. 1 ± 32.4） counts/μg, （ 1821.2± 322. 3 ） counts/（ min. mg） ] as compared with control group [ （ 253.5 ± 29. 8 ） counts/μg, （ 1563.5 ± 272. 4 ） counts/（ min· mg）, P 〈 0. 05 ] before incubation. Superoxide anion levels before incubation were significantly higher than those after incubation with BH4 or LNAME [ （ 1607.4 ± 279. 5 ）, （ 1683.7 ± 267. 9） counts/（ min· mg） ,P 〈 0. 05 ] in test group, and in control group, there was no significant change after incubation with BH4 （ P 〉 0. 05 ） , but superoxide anion levels were increased after incubation with L-NAME [ （ 1721.2 ± 329. 8 ） counts/（ min· mg） ,P 〈 0. 05 ]. There was no significant difference in superoxide anion levels after incubation with heparinized blood between two groups （ P 〉 0. 05 ）. Conclusion The T2MD can aggravate oxidative stress in the great saphenous vein grafts, which may be alleviated by BH4 preservation solution thorough improving the function of endothelial nitric oxide synthase.